I posted a thread in the Sigma section, but I'm think maybe I should ask 70D owners. Just bought the Sigma 18-250mm to replace my Canon 18-55 and 55-250. But I'm realizing that at 250mm, the Canon lens is zooming in closer. 250 on Sigma actually feels more like 200mm.

Can someone explain why? I've been digging through Amazon reviews, and nobody has mentioned this. When searching the internet, I did find someone asking the same question through Yahoo, but there were no good answers.